Las Vegas Motor Speedway will open up one day early for an Sprint Cup Open Test session tomorrow, giving drivers and teams an opportunity to learn more about the Generation 6 cars.

The lighter, sleeker Gen-6 cars – which were designed to improve the racing products on intermediate tracks such as LVMS – continue to be a riddle for everyone in the garage. So far, the new cars have put on two relatively subpar shows at Daytona and Phoenix (with Denny Hamlinbeing particularly pointed in his comments on the subject after the latter race), but at the same time, the learning process remains ongoing.

That, as well as 1.5-mile tracks like LVMS making up the bulk of the calendar, makes Thursday’s test so important for the teams.

“It will help us a ton,” Stewart-Haas Racing crew chief Steve Addington said to NASCAR.com after last weekend’s event at Phoenix. “It’s just learning. It’s going to take us a few races, I think. The Las Vegas test will help (but) it won’t tell us what will happen when we get 43 cars out there again.

“We need to try to get some time to run with a couple of cars and see…how it affects the car on the mile-and-a-half tracks. We’ve got teammates; we can get out there with three cars and see what it does to the cars. We’ve got to use that.”

Teams were able to gain some initial knowledge on the Gen-6 cars at another 1.5-mile oval, Charlotte Motor Speedway, this past January.

As for tomorrow’s test at Vegas, it is expected to run from 8:30 a.m. to 3:30 p.m. PT, and the session will be free and open to the public.